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1.
Int J Mol Sci ; 25(7)2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38612568

ABSTRACT

We have previously shown that PM10 exposure causes oxidative stress and reduces Nrf2 protein levels, and SKQ1 pre-treatment protects against this damage in human corneal epithelial cells (HCE-2). The current study focuses on uncovering the mechanisms underlying acute PM10 toxicity and SKQ1-mediated protection. HCE-2 were pre-treated with SKQ1 and then exposed to 100 µg/mL PM10. Cell viability, oxidative stress markers, programmed cell death, DNA damage, senescence markers, and pro-inflammatory cytokines were analyzed. Nrf2 cellular location and its transcriptional activity were determined. Effects of the Nrf2 inhibitor ML385 were similarly evaluated. Data showed that PM10 decreased cell viability, Nrf2 transcriptional activity, and mRNA levels of antioxidant enzymes, but increased p-PI3K, p-NFκB, COX-2, and iNOS proteins levels. Additionally, PM10 exposure significantly increased DNA damage, phosphor-p53, p16 and p21 protein levels, and ß-galactosidase (ß-gal) staining, which confirmed the senescence. SKQ1 pre-treatment reversed these effects. ML385 lowered the Nrf2 protein levels and mRNA levels of its downstream targets. ML385 also abrogated the protective effects of SKQ1 against PM10 toxicity by preventing the restoration of cell viability and reduced oxidative stress. In conclusion, PM10 induces inflammation, reduces Nrf2 transcriptional activity, and causes DNA damage, leading to a senescence-like phenotype, which is prevented by SKQ1.


Subject(s)
Cornea , NF-E2-Related Factor 2 , Oxidative Stress , Particulate Matter , Humans , Cornea/drug effects , Cornea/metabolism , NF-E2-Related Factor 2/genetics , RNA, Messenger/genetics , Particulate Matter/toxicity
2.
Heliyon ; 9(11): e21451, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38027802

ABSTRACT

Since previous few decays the consideration of non-Newtonian liquids motion due to its immense usages in medicine, biology, industrial procedures, chemistry of catalysts and in environment. Various studies examine the significance of bio-materials flow in physiological procedures to explore the cure of diagnosed symptoms of disease appearing during movement in a human physiological system. To illustrate the characteristics of physiological liquids various non-Newtonian models have been proposed, but yet no such single liquid model is exploited which describes all the properties of nonlinear behaving liquids. Among these several non-Newtonian models, Jeffery liquid model should be reduced to its base fluid case (i.e. viscous liquid) by choosing λ1 = λ2 = 0. Various physiological materials which represents both linear and nonlinear characteristics respectively blood is one of these. Jeffery fluid and peristaltic motion have some common properties such as radii, relaxation time and retardation time. Moreover heat and mass transfer is also an important phenomenon which is suitable for various physiological processes such as hemodialysis and oxygenation etc. Thus due to such motivating facts this research is conducted to investigate the peristaltic motion of electrically conducting Jeffery liquid. The peristaltic propagating channel walls are asymmetric and inclined. Joule heating and magnetic field effects are considered by applying magnetic field in transverse direction to the flow. Further conservation laws modelled the flow situation via considering quadric mix convection, thermos diffusion and diffusion-thermos, heat generation and absorption, chemical reaction with activation energy features. Moreover, creeping flow and long wavelength assumptions are used to simplify the mathematical modelling. The reduced system of equation is solved numerically through built-in technique in Mathematica software. This built-in technique is working through ND Solve command and shooting and RK-Felburg numerical schemes are behind this technique. These numerical results are used to discuss the flow quantities i.e., velocity, temperature and concentration against the sundry dimensionless quantities. Examining the results it comes to know that both thermal and concentration nonlinear mix convection have oppositely affecting the axial velocity. Both heat and mass transfer are escalating function of thermo-diffusion/diffusion-thermo aspects.

3.
Microb Pathog ; 182: 106214, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37423496

ABSTRACT

In this study 269 swabs collected from 254 ovine foot lesions and 15 apparently healthy ovine feet were screened by PCR for the presence of major lameness causing foot pathogens viz. Treponema species, D. nodosus, F. necrophorum and T. pyogenes with the presumption that ovine foot lesion positive for Treponema species alone or in association with other three pathogens were categorized as contagious ovine digital dermatitis (CODD). While samples positive for D. nodosus alone or its combination with F. necrophorum and T. pyogenes were considered as footrot (FR) and samples in which F. necrophorum or T. pyogenes was found either alone or in combination were considered as interdigital dermatitis (ID). The overall occurrence of Treponema sp. in ovine foot lesions was 48.0%, and ranged from 33 to 58%. In Treponema positive samples D. nodosus, F. necrophorum and T. pyogenes were present in 34 (27.4%), 66 (54.4%) and 84 (68.5%) in contrast to Treponema negative samples in which these were present in 15 (11.1%), 20 (14.12%) and 17 (12.6%) samples, respectively. The data signifies that Treponema sp. are significantly associated with these foot pathogens and their different combinations with Treponema sp. influence the severity of CODD lesion. The identification of Treponema phylotypes was done by sequencing the 16S rRNA gene fragment of ten representative samples. Out of ten sequences, four (Trep-2, Trep-4, Trep-7 and Trep-10) were identical to Treponema sp. phylotype 1 (PT1) that belongs to phylogroup T. refringens-like, one sequence (Trep-1) was genetically close (90% sequence homology) to Treponema brennaborense while five sequences (Trep-3, Trep-5, Trep-6, Trep-8 and Trep-9) matched with uncultured bacterium clones of treponemes forming separate monophyletic group in phylogenetic tree and could represent new digital dermatitis phylogroup presently containing five ovine specific phylotypes. This is the first report on the presence of Treponema phylotypes other than three digital dermatitis (DD) Treponema phylogroups viz. T. phagedenis-like, T. medium/T. vincentii-like, and T. pedis-like that are frequently detected in CODD lesions. Metagenomic analysis of two representative samples revealed the abundance of genus Treponema in CODD lesion while this genus was absent in swab collected from clinically healthy foot suggesting that it might play primary role in producing CODD. These findings may further aid in understanding the etiopathogenesis of CODD and could help to develop appropriate treatment and mitigation strategies to combat the disease.


Subject(s)
Cattle Diseases , Digital Dermatitis , Sheep Diseases , Sheep , Animals , Cattle , Digital Dermatitis/epidemiology , Digital Dermatitis/microbiology , Lameness, Animal , Phylogeny , RNA, Ribosomal, 16S/genetics , Treponema/genetics , Sheep, Domestic/genetics , Sheep Diseases/microbiology , Cattle Diseases/microbiology
4.
Comput Biol Med ; 155: 106699, 2023 03.
Article in English | MEDLINE | ID: mdl-36857941

ABSTRACT

Current analysis highlights the aspects of different nanoparticles in peristalsis with entropy generation. Mathematical equations of considered problem are modelled via conservation laws for mass, momentum and energy. Such equations contain variable viscosity, nonlinear thermal radiation, viscous dissipation, heat generation/absorption and mixed convection aspects. Boundary conditions comprise the second order velocity and first order thermal slip effects. Entropy expression is obtained by utilization thermodynamics. Simplified and dimensionless forms of the considered conservative laws are obtained through lubrication technique. Resulting system of equations subject to the considered boundary conditions is solved numerically via built-in shooting procedure in Mathematica. Such numerical procedure is very suitable to obtain numerical results directly and fastly in the form of graphs. Further all the considered flow quantities are discussed graphically for the significant parameters of interest in detail. Both velocity and temperature are decreasing against large volume fraction parameter. Increasing temperature dependent viscosity effects decrease the entropy and enhance the Bejan number.


Subject(s)
Models, Theoretical , Nanostructures , Entropy , Viscosity , Peristalsis
6.
Int J Tuberc Lung Dis ; 26(8): 741-746, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35898140

ABSTRACT

BACKGROUND: We assessed treatment uptake and completion for 6 months of isoniazid (6H) and 3 months of isoniazid plus rifapentine weekly (3HP) in a programmatic setting in Pakistan.METHODS: All household contacts were clinically evaluated to rule out TB disease. 6H was used for TB preventive treatment (TPT) from October 2016 to April 2017; from May to September 2017, 3HP was used for contacts aged ≥2 years. We compared clinical evaluation, TPT uptake and completion rates between contacts aged ≥2 years in the 6H period and in the 3HP period.RESULTS: We identified 3,442 contacts for the 6H regimen. After clinical evaluation, 744/1,036 (72%) started treatment, while 46% completed treatment. In contrast, 3,722 contacts were identified for 3HP. After clinical evaluation, 990/1,366 (72%) started treatment, while 67% completed treatment. Uptake of TPT did not differ significantly between the 6H and 3HP groups (OR 1.03, 95%CI 0.86-1.24). However, people who initiated 3HP had 2.3 times greater odds (95% CI 1.9-2.8) of completing treatment than those who initiated 6H after adjusting for age and sex.CONCLUSION: In programmatic settings in a high-burden country, household contacts of all ages were more likely to complete TPT with shorter weekly regimens, although treatment uptake rate for the two regimens was similar.


Subject(s)
Isoniazid , Latent Tuberculosis , Antitubercular Agents/therapeutic use , Drug Therapy, Combination , Humans , Isoniazid/therapeutic use , Latent Tuberculosis/drug therapy , Pakistan/epidemiology
7.
Braz J Biol ; 84: e261446, 2022.
Article in English | MEDLINE | ID: mdl-35830131

ABSTRACT

Asiatic black bear has long been in conflict with human beings crop raiding is a major cause of this conflict frequently noted in South Asia. Crops raided by black bears affected by temporal, spatial and anthropogenic attributes. Insight in this conflict and its mitigation is vital for the conservation of this threatened species. Present study aimed to evaluate crop raiding by black bears in the mountainous region of Azad Jammu and Kashmir. Field surveys were carried out to observe spatial and temporal crop raiding features between 2015-2020 and data gathered using designed questionnaires randomly tailored in villages nearby the forests. Results revealed that maize was the sole crop raided by black bears. A total of 28-acre area was raided by black bear in the fall season (Aug-November) resulting in a damage of 51 metric tons, whole raiding was carried out at night. Each respondent received crop damage on 0.09 acre with a loss of 0.17 metric ton yield. Crop quantity and area were significantly correlated to each other. District Neelum shared 49% of the total crop loss, while 47% of the maize was raided at the altitudinal range of 2100-2500 m. crop raiding was highly significantly ( χ 2 = 1174.64 ; d f = 308 ;   p < 0.01 ) dependent upon distance to the forest. Linear regression revealed that maize quantity was determined by area, time and the total field area. Farmers faced 3.8 million PKRs loss due to crop damage by black bears. Despite the huge loss, the majority (23%) of the respondents did not respond to the query on mitigation measures indicating a poor adaptation of preventive measures. Preferred strategy to avoid crop damage was making noise (27.8%) when bears attacked their crops. A start of compensation scheme to the farmers is recommended that will have turned their negative attitude into a positive one toward the wildlife and black bear particularly. Study provides a new insight in human-bear conflict, particularly in spatial and temporal context of crop raiding in AJ&K.


Subject(s)
Ursidae , Animals , Conservation of Natural Resources/methods , Crops, Agricultural , Forests , Humans , Pakistan
8.
Sci Total Environ ; 825: 153986, 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35189210

ABSTRACT

Coastal lagoons experience removal and leaching of metals due to seasonal fluctuation of salinity coupled with pH and dissolved oxygen variability. Benthic foraminifers are susceptible to seasonal variation in physicochemical conditions. Assessment of bioavailable fraction of selected metals in sediments along the salinity gradient of the largest brackish lagoon in Asia- Chilika was carried out. Further, population density and abnormality index of foraminifera in the sediments were calculated to understand the influence of bioavailable metal on benthic foraminifera. Metal concentrations were higher in the low salinity regions and decreased towards the high salinity regions. This suggests river discharge controls the metal input and distribution in the lagoon. Overall, metal concentrations are high in the residual fraction (F4) followed by interplay within the reducible (F2) or oxidizable (F3) fractions, except for Mn. The seasonal fluctuations of pH and cyclic oxygen deficiency intensified the leaching of Fe, Cr, Cu, Pb, and Zn in the bioavailable fraction in the low salinity region of the lagoon. The presence of metals in bioavailable fractions impacted the normal growth of the abundant Ammonia species. Despite low bioavailable metal concentrations, higher morphological abnormalities were observed in the high salinity regions due to higher energy conditions near the sea. Therefore, abnormalities in the benthic foraminifera are attributed to bioavailability of metals from sediments and natural stress conditions in the coastal lagoon environment.


Subject(s)
Foraminifera , Metals, Heavy , Water Pollutants, Chemical , Biological Availability , Environmental Monitoring , Geologic Sediments , Metals, Heavy/analysis , Rivers , Water Pollutants, Chemical/analysis
9.
J Ultrason ; 21(86): e186-e193, 2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34540271

ABSTRACT

Aim: In this study, we sought to examine the optimal cutoff values for predicting different stages of liver fibrosis, and to determine the level of agreement between shear wave elastography and aspartate aminotransferase to platelet ratio index (APRI) and fibrosis-4 index (FIB-4) scores in patients with chronic liver disease. Methodology: A descriptive, cross-sectional study was performed at the Radiology Department of Shaukat Khanum Memorial Hospital Lahore from 1 Jun 2019 until 1 June 2020. FIB-4 and APRI scores were determined by the following formula: FIB-4 = (age × AST) ÷ (platelet count × (√ (ALT)) and APRI = (AST÷AST upper limit of normal) ÷ platelet × 100. Data was analyzed with the help of SPSS version 24.0 and Microsoft Excel 2013. Results: Eighty individuals were conveniently selected, of which 62.5% were men and 37.5% were women. The mean age of the subjects was 43.47 SD ± 13.85 years. APRI and FIB-4 scores predicted F4 patients using the cutoff values of 0.47 (Sn. 72%, Sp. 70%) and 1.27 (Sn. 78%, Sp. 73%), respectively. The cutoff values of 0.46 for APRI and 1.27 for FIB-4 predicted F3-F4 patients (Sn. 74% and 77%; Sp. 76% and 76%), respectively. To predict F1-F4 compared to F0, the cutoff value was 0.34 (Sn. 68%, Sp. 75%) for APRI, while the cutoff value for FIB was 0.87 (Sn. 72%, Sp. 75%). The findings suggest that FIB-4 shows better diagnostic accuracy than APRI. Conclusion: This study provides optimal cutoff values for different groups of fibrosis patients for both serum markers. Also, the diagnostic accuracy of FIB-4 for predicting liver fibrosis was found to be superior to APRI in all disease stages.

12.
Chromosome Res ; 29(1): 19-36, 2021 03.
Article in English | MEDLINE | ID: mdl-33686484

ABSTRACT

The organization of chromatin into higher-order structures and its condensation process represent one of the key challenges in structural biology. This is important for elucidating several disease states. To address this long-standing problem, development of advanced imaging methods has played an essential role in providing understanding into mitotic chromosome structure and compaction. Amongst these are two fast evolving fluorescence imaging technologies, specifically fluorescence lifetime imaging (FLIM) and super-resolution microscopy (SRM). FLIM in particular has been lacking in the application of chromosome research while SRM has been successfully applied although not widely. Both these techniques are capable of providing fluorescence imaging with nanometer information. SRM or "nanoscopy" is capable of generating images of DNA with less than 50 nm resolution while FLIM when coupled with energy transfer may provide less than 20 nm information. Here, we discuss the advantages and limitations of both methods followed by their contribution to mitotic chromosome studies. Furthermore, we highlight the future prospects of how advancements in new technologies can contribute in the field of chromosome science.


Subject(s)
Chromatin , Chromosomes , Chromosomes/genetics , Microscopy, Fluorescence
13.
Curr Microbiol ; 78(4): 1298-1304, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33638672

ABSTRACT

The aim of this study was to identify the immunodominant outer membrane proteins (OMPs) of Fusobacterium necrophorum from sheep affected with severe foot-rot. The OMP profile of ovine strains of F. necrophorum has not been well studied. We analyzed the OMP profile of the most frequent lktA variant JKS-F3 of F. necrophorum associated with severe ovine foot-rot with lesion score 4 in order to identify its major immunodominant OMPs. Electrophoretic separations of extracted OMPs showed a number of spots in two-dimensional electrophoretic gels. Two immunoreactive proteins of size around 43 kDa were identified through western blotting using hyperimmune sera raised in rabbits. These two immunogenic OMPs were analyzed by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF/MS) which revealed that these two OMPs of lktA variant JKS-F3 of F. necrophorum showed 46 and 42 percent protein sequence coverage and scores of 125 and 114, respectively, with the reported 43 kDa outer membrane protein of F. necrophorum strain H05, a putative porin having properties similar to pore-forming proteins of anaerobic Gram-negative bacteria. These identified immunogenic OMPs will contribute to our understanding of the pathogenic role played by this organism in ovine foot-rot and could be exploited to devise an effective control strategy through development of an OMP-based recombinant vaccine to mitigate foot-rot in sheep and goats.


Subject(s)
Foot Rot , Fusobacterium necrophorum , Animals , Bacterial Outer Membrane Proteins/genetics , Goats , Membrane Proteins , Rabbits , Sheep , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
14.
Int J Tuberc Lung Dis ; 24(10): 1067-1072, 2020 10 01.
Article in English | MEDLINE | ID: mdl-33126941

ABSTRACT

BACKGROUND: Addressing TB in India is critical to meeting global targets. With the scale-up of diagnostic networks and the availability of new TB drugs, India had the opportunity to improve the detection and treatment outcomes in drug-resistant TB (DR-TB).OBJECTIVE: To document how the introduction of new drugs and regimens is helping India improve the care of DR-TB patients.DESIGN: In 2016, India´s National TB Programme (NTP) introduced bedaquiline (BDQ) under a Conditional Access Programme (BDQ-CAP) at six sites after providing extensive training and strengthening laboratory testing, pre-treatment evaluation, active drug safety monitoring and management (aDSM) and follow-up systems.RESULTS: An interim analysis reflected earlier and better culture conversion rates: 83% of the 620 patients converted within a median time of 60 days. However, 248 serious adverse events were reported, including 73 deaths (12%) and 100 cardiotoxicity events (16.3%). Encouraged by the evidence of safety and efficacy of BDQ, the NTP took steps to systematically expand its access to cover the entire population by 2018.CONCLUSION: The cautious yet focused approach used to introduce BDQ under BDQ-CAP paved the way for the rapid introduction of delamanid, as well as the shorter treatment regimen and the all-oral regimen for DR-TB.


Subject(s)
Pharmaceutical Preparations , Tuberculosis, Multidrug-Resistant , Antitubercular Agents/adverse effects , Diarylquinolines/adverse effects , Humans , India , Tuberculosis, Multidrug-Resistant/drug therapy
15.
Lett Appl Microbiol ; 71(6): 627-636, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32867004

ABSTRACT

Bovine genital campylobacteriosis caused by Campylobacter fetus subsp. venerealis (Cfv) is of considerable economic importance to the cattle industry worldwide. Cfv causes syndrome of temporary infertility in female cattle, early embryonic mortality, aberrant oestrus cycles, delayed conception, abortions and poor calving rates. In the present study, a total of 200 samples obtained from vaginal swabs, cervicovaginal mucous (CVM), preputial washes and semen straws were investigated that were obtained from organized cattle farm of MLRI, Manasbal and unorganized sectors. Out of a total of 200 samples, 49 (47·57%) vaginal swabs, 1 (3·33%) preputial wash and 8 (25%) carried out CVM samples were positive for Cfv, whereas none of the semen straws were positive for Cfv. A total of eleven isolates of Cfv were recovered. PFGE (Pulse field gel electrophoresis) analysis revealed four different pulsotypes (I-IV) circulating in the screened farms. A common pulsotype circulating among farms could not be established. Insertion element (ISCfe1), a 233 bp amplicon of Cfv, was sequenced and the sequence was deposited in GenBank (accession no: MK475662).


Subject(s)
Campylobacter Infections/veterinary , Campylobacter fetus/drug effects , Campylobacter/drug effects , Cattle Diseases/microbiology , Animals , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Campylobacter/classification , Campylobacter/genetics , Campylobacter/isolation & purification , Campylobacter Infections/microbiology , Campylobacter fetus/classification , Campylobacter fetus/genetics , Campylobacter fetus/isolation & purification , Cattle , DNA Transposable Elements , Drug Resistance, Bacterial , Farms , Female , Genotype , India , Male
16.
Int J Tuberc Lung Dis ; 24(7): 665-673, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32718398

ABSTRACT

BACKGROUND: Systematic screening for TB using automated chest radiography (ACR) with computer-aided detection software (CAD4TB) has been implemented at scale in Karachi, Pakistan. Despite evidence supporting the use of ACR as a pre-screen prior to Xpert® MTB/RIF diagnostic testing in presumptive TB patients, there has been no data published on its use in mass screening in real-world settings.METHOD: Screening was undertaken using mobile digital X-ray vehicles at hospital facilities and community camps. Chest X-rays were offered to individuals aged ≥15 years, regardless of symptoms. Those with a CAD4TB score of ≥70 were offered Xpert testing. The association between Xpert positivity and CAD4TB scores was examined using data collected between 1 January and 30 June 2018 using a custom-built data collection tool.RESULTS: Of the 127 062 individuals screened, 97.2% had a valid CAD4TB score; 11 184 (9.1%) individuals had a CAD4TB score ≥70. Prevalence of Xpert positivity rose from 0.7% in the <50 category to 23.5% in the >90 category. The strong linear association between CAD4TB score and Xpert positivity was found in both community and hospital settings.CONCLUSION: The strong association between CAD4TB scores and Xpert positivity provide evidence that an ACR-based pre-screening performs well when implemented at scale in a high-burden setting.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Tuberculosis , Aged , Humans , Mass Screening , Pakistan/epidemiology , Radiography , Sensitivity and Specificity , Tuberculosis/diagnosis , Tuberculosis/epidemiology , Tuberculosis, Pulmonary/diagnostic imaging , Tuberculosis, Pulmonary/epidemiology
17.
Hepatobiliary Surg Nutr ; 9(1): 13-24, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32140475

ABSTRACT

BACKGROUND: Patients with advanced hepatobiliary cancer (HBC) have a dismal prognosis and limited treatment options. Immunotherapy has been considered as a promising treatment, especially for cancers not amenable to surgery. METHODS: Between 2004, and 2015, patients diagnosed with hepatocellular carcinoma (HCC), intra- and extrahepatic cholangiocarcinoma and gallbladder cancer (GBC) were identified in the National Cancer Database. RESULTS: Among 249,913 patients with HBC, only 585 (0.2%) patients received immunotherapy. Among patients who received immunotherapy, most patients were diagnosed between 2012 and 2015, had private insurance, as well as an income ≥$46,000 and were treated at an academic facility. The use of immunotherapy among HBC patients varied by diagnosis (HCC, 67.7%; bile duct cancer, 14%). On multivariable analysis, a more recent period of diagnosis (OR 1.80, 95% CI: 1.44-2.25), median income >$46,000 (OR 1.43, 95% CI: 1.11-1.87), and higher tumor stage (stage III, OR 2.22, 95% CI: 1.65-3.01; stage IV, OR 3.24, 95% CI: 2.41-4.34) were associated with greater odds of receiving immunotherapy. CONCLUSIONS: Overall utilization of immunotherapy in the US among patients with HBC was very low, yet has increased over time. Certain socioeconomic factors were associated with an increased likely of receiving immunotherapy, suggesting disparities in access of patients with lower socioeconomic status.

18.
Comput Methods Programs Biomed ; 190: 105252, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32059157

ABSTRACT

In this published paper, a mathematical modeling has been conducted for the peristaltic transport in flow of hybrid nanofluid between rotating channel in the presence of nonlinear thermal radiation, slip effects and entropy generation. This corrigendum correct the flow geometry, figures captions and plots "Transport of hybrid type nanomaterials in peristaltic activity of viscous fluid considering nonlinear radiation, entropy optimization and slip effects" [Computer Methods and Programs in Biomedicine 184 (2020) 105,086] where these mistake are occurred during production process and therefore, some captions are shuffled. The difference in the captions and plots however does not affect the authenticity and mathematical validity of the problem in purpose of this published research article is to investigate the peristaltic transport in flow of hybrid nanofluid between rotating channel subject to nonlinear thermal radiation, slip effects and entropy generation. However, the flow geometry and the captions and plots should be arranged.


Subject(s)
Algorithms , Hydrodynamics , Nanostructures , Computer Graphics , Entropy , Viscosity
19.
Comput Methods Programs Biomed ; 190: 105355, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32058189

ABSTRACT

BACKGROUND: Peristaltic is a basic way of fluid transportation in physiology, engineering and nuclear industry. Importance of peristalsis is due to its contraction and compulsion property of symmetric and asymmetric type channel walls. Another beauty of this mechanism is that the channel walls propagates and push the material along the tube/conduit channel walls. This mechanism shows its presence in physiology while food particles are transferred through esophagus and stomach, urine through intestines, spermatoza transportation in reproductive tract. In industry it is found in roller and finger pumps, drug delivery and various nuclear materials e.g. toxic, corrosive, noxious etc. Magnetic field in peristalsis is found helpful in treatment of various treatments using magnets. Actually earth and human body as a whole comprises of magnetic and electric fields. The medical specialists found that unbalances of electromagnetic field in human body is the reason for emotional and physical disturbance. In addition it has significant and potential utilizations in modification of medical, industrial and chemical, procedures for example MRI, evaporation, convection, thermoregulation, MHD throttles, and in various types of tumor treatments. Entropy production work out irreversibility in complex systems which are frequently encountered in industrial mechanisms. In view of that, this methodology is effectually implemented in distinct technological applications covering porous media, propulsion ducts, electronic cooling, turbo-machinery and combustion. METHOD: Modelled flow mechanism is nonlinear and coupled due to considered assumptions (i.e. nanofluid, nonlinear porous channel, mixed convection, variable viscosity and thermal conductivity, activation energy and chemical reaction). Such nonlinear and coupled system is difficult to tackle analytically. Thus to obtain the solution we employed RK algorithm for numerical simulations. RESULTS: Stronger magnetic parameter shows resistive characteristics to the flow field. Nonlinear Darcy medium assists the fluid motion at channel center and resits at walls vicinity. Variable characteristics of thermal conductivity moderate the soak or disperse up heat ability which corresponds to temperature reduction. Thermal slip quantity increase the temperature whereas concentration slip deduct the concentration of Carreau nanomaterial. Entropy and Bejan number shows maximum response for higher dissipation estimations. Brownian and thermopherotic motions aspects has reverse impact on nanomaterial concentration. CONCLUSION: Entropy and Bejan number deduces for higher variable thermal conductivity values. Carreau material variable enhance the entropy of the system as a whole.


Subject(s)
Hot Temperature , Hydrodynamics , Nanostructures , Peristalsis , Thermal Conductivity , Viscosity , Algorithms , Humans
20.
Comput Methods Programs Biomed ; 186: 105045, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31734470

ABSTRACT

OBJECTIVE AND BACKGROUND: This article featuring the peristaltic transport of viscous material with variable properties (i.e. temperature dependent viscosity and thermal conductivity) through curved configuration. Fluid saturating through porous channel walls of uniform space. Entropy generation consideration here is to analyze irreversibility aspects. Channel boundaries retain the velocity and thermal slip conditions. METHOD: Wave frame of reference is attained with the utilization of long wavelength and small Reynolds number approach. Solution of the simplified coupled system of dimensionless constraints is obtained numerically. Detailed analysis of important quantities of interest has been presented in discussion portion. RESULTS: Entropy generation variation near center is very small whereas in the vicinity of the channel wall is larger. Bejan number has reverse variation as observed for entropy generation. CONCLUSION: Variable characteristics of viscosity has opposite impact on velocity and temperature is observed. It is also noticed small irreversibility effects are obtained for higher varying viscosity and thermal conductivity near the vicinity of the channel walls.


Subject(s)
Entropy , Magnetics , Viscosity , Thermal Conductivity
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